What element has two valence electons?

Answer 1

Here at Afuelscience.com we use this method...the number of valence electrons is the number of s and p electrons in the outermost shell (highest n). The number of valence electrons can also be determined by counting across the period, skipping the transition metals, until the element is reached. It is also the group number. If there is more than one atom, the number of valence electrons is the sum of all the atoms in the molecule or polyatomic ion. For ions, add the value of a negative charge and subtract the value of a positive charge. >> Example 1 How many valence electrons are in the following? # N # H2S # CO32- # NH4+ Solution: # Nitrogen is in group 5A. It has five valence electrons. # Hydrogen has one valence electron, and sulfur has six. The total for the molecule is 2(1) + 6 = 8. # Carbon has four valence electrons; oxygen has six; then two for the charge. 4 + 3(6) + 2 = 24. # Nitrogen has five valence electrons; hydrogen has one, minus one for the charge. 5 + 4(1) - 1 = 8.

Answer 2

I think you mean "what elements have two electrons in the valence shell". The elements that are thought to have two valence electrons are the elements in the second column of the periodic table, (e.g. Mg - magnesium, Ca - calcium, etc.). He - helium is also known to have two valence electrons.

Answer 3

The elements in Group II in the Periodic Table:

Beryllium

Magnesium

Calcium

Strontium

Barium

Radium